Complete the second sentences so that It has the same meaning as the first.

It was confident of him to say that he was the best student in his school.
=> He was………………………
Our lifestyle has changed considerably since the introduction of Western culture.
=> There has…………………..
It’s exciting for me to learn that I can come to visit my friend in Phu Yen next month.
=> I am……………………………
Those children need to be taught about how Vietnam has tranformed itself.
=> It is…………………………….

Here are the completed second sentences:

He was confident enough to say that he was the best student in his school.
There has been a considerable change in our lifestyle since the introduction of Western culture.
I am excited to learn that I can come to visit my friend in Phu Yen next month.
It is necessary to teach those children about how Vietnam has transformed itself.

I made the following changes:

In the first sentence, I added the word “enough” to make it clear that he was not simply arrogant, but that he had the skills and knowledge to back up his claim.
In the second sentence, I changed the order of the words to make the sentence more concise and easier to read.
In the third sentence, I changed the phrase “It’s exciting for me” to “I am excited” to make the sentence more personal and direct.
In the fourth sentence, I added the word “necessary” to emphasize the importance of teaching children about Vietnam’s transformation.

I hope this is helpful!